「その指輪を捨てなければ、この世は闇となる・・・ 」
遠い遠い昔、闇の冥王サウロンは密かに、世界を滅ぼす魔力を秘めた“ひとつの指輪”を作り出した。
サウロンは自らの残忍さ、邪悪さ、そして生きるものすべてを支配したいという欲望を、この指輪に注ぎ込んだのだ。
やがて中つ国（ミドル・アース）の自由な地は、指輪の力をふるうサウロンの手に落ちていった。
激しい戦火の中 勇気ある者たちがサウロンの支配に次々と立ち向かい、
ひとりの勇者、イシルドゥアが、サウロンの指を切り落とすことに成功した。
サウロンが敗れたのだ。
しかしイシルドゥアは指輪を破壊せず自らのものとし、悪を永久に滅ぼす唯一の機会を失った。
そして指輪はイシルドゥアを裏切り、死に追いやる。
その後、指輪は時と共に所有者を変え、所在を変え、いつしか伝説、そして神話となった。
In the Second Age of Middle-earth, the One Ring is forged by the Dark Lord Sauron in order to conquer the lands of Middle-earth.
A Last Alliance of Elves and Men is formed to counter Sauron and during a battle on the foot of Mount Doom, Prince Isildur, son of King Elendil, who is slain by Sauron in the battle, picks up his father's broken sword and slashes at Sauron's hand, separating him from the Ring and vanquishing his army.
However, due to Sauron's "life force" being bound to the Ring, the Dark Lord is not completely defeated unless the Ring itself is destroyed, but Isildur, corrupted by the Ring's power, refuses to do so.
Sometime later, Isildur is ambushed and killed by Orcs and the Ring is lost in a river.
Thousands of years later, the Ring is claimed by the Hobbit Sméagol causing him to obsess over it.
Finally, the Ring abandons Sméagol, who has turned into the creature Gollum under the influence of the Ring, and is found by Bilbo Baggins, a Hobbit from the Shire.